.75 - 3/4"
2 - 2"
24 - 24"
30 - 30"
The coded value domain includes both the actual value that is stored in the database, for example, 1 for pavement, and a description of what the code value means, for example, pavement.

Procedure
In ArcCatalog, right-click on the data connection, click Properties, and then select the Domains tab.

Select a domain from the list and add a new coded value with a description.

Associate the updated domain with a feature class field using the 'Assign Domain To Field' tool in ArcToolBox. This is available by navigating to ArcToolbox > Data Management Tools > Domains > Assign Domain to Field.

Start ArcMap with a new blank map document. Drag and drop the layer with the field specified to use the updated domain from ArcCatalog to ArcMap. Close ArcCatalog.
Start an edit session in ArcMap. The coded value can now be selected in the attribute table.